In last years, the Portuguese economy has gone through a severe adjustment process, affecting almost all industrial sectors, the building blocks of economic structures. Research on economic structural changes has made use of input/output tables to define networks of industrial relations. Here, these networks are induced from output tables of the Portuguese national accounting system, being each inter-industry relation defined by the output made by any two industries for the products that they both produce. The topological analysis of these networks allows to uncover a particular structure that comes out during the Portuguese adjustment program. The evolution of the industrial networks shows an important structural change in 2011-2014, confirming the usefulness of inducting similarity networks from output tables and the consequent promising power of the graph formulation for the analysis of inter-industry relations.